(714) 688-1500   pcboards@rigiflex.com

Flex & Rigid-Flex PCBs.. 1-5 Day Quick Turn


Superior & Trusted Flexible, Rigid-Flex & Rigid PCBs for Over 25 years


HDI (HIGH DENSITY INTERCONNECT PCBS) is one of the fastest growing technologies aimed to increase the functionality of conventional PCBs. Owing to increased, density they provide the necessary routing solutions for large pin-count chips that are utilized in mobile devices and other high tech products.

Features of HDI

There are several key features of HDI PCBs, some of which are as given below:

  • HDI PCBs are characterized by high-density laser microvias, fine lines and high performance thin material.
  • HDI boards offer higher circuitry density in comparison to traditional circuit boards which further enhances their electrical performance.
  • HDI PCBs have multiple layers of copper filled, stacked microvias which create a structure that enables even more complex interconnections.
  • These boards include micro-sized holes, which can be constructed with high performance materials, thereby enabling more interconnection functions per unit area.
  • In comparison to the standard circuit, HDIs deploy ultra-thin cores which helps reduce the size and weight of components.

HDI Builds

HDI PCBs have a much higher wiring and pad connection density than traditional PCBs, due to their design constraint. The structural build up is explained below.

  • 1+N+1 – PCBs contain 1 “build-up” of high-density interconnection layers.
  • i+N+i (i ≥ 2) – PCBs contain 2 or more “build-up” of high density interconnection layers. Microvias on different layers can either be staggered or stacked up.
  • Any Layer HDI – The layers of a PCB are high density interconnection layers which allow the conductors on any layer of the PCB to be interconnected freely with copper filled stacked microvia structures.

HDI’s Capability

By using HDI technology, designers now have the option to place more components on both sides of a raw PCB. Below are the capabilities of HDIs.

Technical Specification

Number of layers

4 – 22 layers standard, 30 layers advanced


FR4 standard, FR4 high performance, Halogen free FR4, Rogers

Copper weights (finished)

18μm – 70μm

Minimum track and gap

0.075mm / 0.075mm

PCB thickness

0.40mm – 3.20mm

Maximum dimensions

610mm x 450mm; dependent upon laser drilling machine

Surface finishes available

OSP, ENIG, Immersion tin, Immersion silver, Electrolytic gold, Gold fingers

Minimum mechanical drill


Minimum laser drill

0.10mm standard, 0.075mm advanced


HDI PCBs are utilized to meet the market demand for complex designs PCB in smaller form factors across the majority of market segments.

  • Automotive Industries: Engine Control Units, GPS, Dashboard Electronics.
  • Telecom Industries: Computers, Laptops, Tablets, Wearable Electronics, Internet of Things
  • Military: Military Routers, COTS Boards, etc.
  • Medical: 35 Micron trace space board, Pacemakers
  • Semiconductors: MCM / Flip Chip / Wirebond, stacked microvias

This advancement in PCB technology is driven by the miniaturization of components and semiconductor packages that support advanced features in revolutionary new products. The professionals at Rigiflex are always ready to provide you with the best service. For more information, give us a call at 714-688-1500.

Quick Contact

All Fields are Mandatory (*)



Need it quick? That is our speciality!